> Source: [sk163314](https://support.checkpoint.com/results/sk/sk163314)

# sk163314 - Some connections dropped due to incorrect NAT, when using IP pool NAT for Multicast connections

| Property | Value |
|----------|-------|
| Solution ID | sk163314 |
| Date Created | 2019-10-30 |
| Last Modified | 2020-01-29 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- Some connections will be dropped due incorrect NAT, when using IP pool NAT for Multicast connections.

## Cause

This issue is due to I/S changes that were integrated in R80.20

As a result of these changes, NAT is calculated on the inbound traffic. Consequently, we do not know from which interface the Multicast traffic will be delivered.

## Solution

This solution requires authentication. Please log in to view the full solution.

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